$OpenBSD: patch-Makefile,v 1.1 2017/04/18 13:09:23 sthen Exp $
--- Makefile.orig	Tue Apr 18 14:06:16 2017
+++ Makefile	Tue Apr 18 14:06:23 2017
@@ -1,8 +1,8 @@
 CC = gcc
 CXX = g++
 
-CFLAGS = -W -Wall -Wextra -ansi -pedantic -lm -O2
-CXXFLAGS = -W -Wall -Wextra -ansi -pedantic -O2
+CFLAGS = -W -Wall -Wextra -ansi -pedantic -lm $(COPTFLAGS)
+CXXFLAGS = -W -Wall -Wextra -ansi -pedantic $(COPTFLAGS)
 
 ZOPFLILIB_SRC = src/zopfli/blocksplitter.c src/zopfli/cache.c\
                 src/zopfli/deflate.c src/zopfli/gzip_container.c\
